Why you should do all of your important tasks in the first half of your day

Do you ever notice that by the time 3 p.m. starts to roll around, your brain kind of checks out for the day? Well, there’s a scientific reason for that—and you might want to rethink your daily schedule because of it, especially if you’re sleep-deprived.

Instead of waiting to do your important tasks in the afternoon, check everything off your list in the morning: In a new study, researchers found your brain slows down throughout the day due to a lack of sleep, and that causes delayed behavioral responses, as well as trouble with memory associations and visual perception. Yikes.

“Sleepiness slows down the responses of individual neurons, leading to behavioral lapses.” —Yuval Nir, PhD

“Performing [tasks are] difficult when we’re tired and especially after pulling an all-nighter,” said lead study author Yuval Nir, PhD, in a press release. “The data gleaned from the experiment afforded us a unique glimpse into the inner workings of the human brain. It revealed that sleepiness slows down the responses of individual neurons, leading to behavioral lapses.”

Since researchers found those behavioral lapses cause slow, weak, and sluggish responses, it’s all the more reason to get a proper amount of sleep every night—no skimping! But if you do stay up too late (it happens!), complete your most crucial duties in the first half of the day. You know, before your brain says “see ya!”

Here are 9 warning signs that exhaustion is right around the corner. Also, check out these 7 surprising reasons you’re feeling fatigued.